Type

Rigel runs on three type faces with hard boundaries between them. Each face owns a role, and crossing those boundaries is a defect, not a style choice. For the palette these faces sit on, see color.md; for the counter-star R mark, see identity.md. The two font stacks are defined in apps/ui/src/design/tokens.css.

The three faces

• RIGEL bitmap — the in-house heavy bitmap counter-star R. The mark only: the icon and the wordmark’s leading R. Never body copy, never UI labels, never headlines. It exists as SVG geometry, not a font file.
• Departure Mono — the wordmark’s trailing I-G-E-L and brand display moments. It is a bitmap face used for large brand display at 11px multiples only (see the constraint below).
• Space Mono (Colophon, OFL) — the body/UI workhorse (--rigel-mono), chosen over IBM Plex Mono for retro-futurist character while staying legible at 12px; Plex is kept as the fallback in the --rigel-mono stack. Everything ≤16px and every off-grid size uses --rigel-mono.

The Departure-Mono 11px-grid constraint

Departure Mono is a bitmap face with UPM 550 (= 11 × 50), so its design grid is 11px tall: it renders pixel-clean at integer multiples of 11px and goes soft at every off-grid size (12/14/16px are muddy).

There is a finer crispness detail: the face is truly crisp only at even 11px multiples (22/44/66/88), because those land on whole device pixels across the common DPR range. Odd multiples like 33px smear at fractional DPR (125/150/175%), so even multiples are the safe display sizes.

The standing rule: Departure is for large brand display at 11px multiples only; everything ≤16px and every off-grid size uses --rigel-mono (Space Mono, hinted TrueType, crisp at any size). The constraint is documented at the --rigel-display token in apps/ui/src/design/tokens.css.

The token stacks

The two font stacks, verbatim from apps/ui/src/design/tokens.css:

--rigel-mono: "Space Mono", "IBM Plex Mono", ui-monospace, monospace;
--rigel-display: "Departure Mono", "Space Mono", monospace;

Requirement: Departure Mono is used only for large display at 11px multiples

Departure Mono (--rigel-display) SHALL be used only for large brand display at integer multiples of 11px (11, 22, 33, 44…); every size ≤16px and every off-grid size SHALL use --rigel-mono (Space Mono), which stays crisp at any size.

Scenario: a heading or label needs a type face

• Given text at a size that is ≤16px or not a multiple of 11px
• When its face is chosen
• Then it uses --rigel-mono (Space Mono), not --rigel-display, so it renders crisp rather than soft.